Low foaming detergent

ABSTRACT

A COMPOSITION ADAPTED TO BE FORMULATED WITH AUTOMATIC DISHWASHING DETERGENTS FOR REDUCING FOAM DURING USE THEREOF IN THE PRESENCE OF PROTEINACEOUS MATTER, COMPRISING (A) ABOUT 95.0 TO 99.5 WEIGHT PRRCENT OF A NONIONIC SURFACE ACTIVE AGENT AND (B) ABOUT 0.5 TO 5.0 WEIGHT PERCENT OF (A) ALKYL PHOSPHATE ESTER HAVING 18 CARBON ATOMS IN THE ALKYL RADICAL PLUS (B) OXYETHYLATED AMINES SELECTED FROM THE GROUP CONSSTING OF AN OXYETHYLATED MONO OR DI ALKYL AMINE OR A MONO OR DI (HYDROXY ALKYL) AMINE WHEREIN THE ALKYL GROUP CONTAINS ABOUT 10 TO 20 CARBON ATOMS AND THE OXYETHYLENE PORTION CONTAINS 1 TO 50 UNITS, THE WEIGHT RATIO OF SAID ALKYL PHOSPHATE ESTER (A) TO SAID OXYETHYLATED FATTY AMINE (B) BEING FROM ABOUT 2:1 TO 1:2.

United States Patent Ofice 3,741,912 LOW FOAMIN G DETERGENT Thomas M. Kaneko, Trenton, Mich., assignor to BASF Wyandotte Corporation, Wyandotte, Mich.

No Drawing. Continuation-impart of application Ser. No. 786,350, Dec. 23, 1968. This application Nov. 19, 1971, Ser. No. 200,610

Int. Cl. B01d 19/04; C011d 1/66, N34 US. Cl. 252-529 5 Claims ABSTRACT OF THE DISCLOSURE A composition adapted to be formulated with automatic dishwashing detergents for reducing foam during use thereof in the presence of proteinaceous matter, comprising:

(A) about 95.0 to 99.5 weight percent of a nonionic surface active agent and (B) about 0.5 to 5.0 weight percent of (a) alkyl phosphate ester having 18 carbon atoms in the alkyl radical plus (b) oxyethylated amines selected from the group consisting of an oxyethylated mono or di alkyl amine or a mono or di (hydroxy alkyl) amine wherein the alkyl group contains about to 20 carbon atoms and the oxyethylene portion contains 1 to 50 units, the weight ratio of said alkyl phosphate ester (a) to said oxyethylated fatty amine (b) being from about 2:1

This application is a continuation-in-part application of US. patent application Ser. No. 786,350 filed Dec. 23, 1968, now abandoned, entitled, Low Foaming Detergent.

It is known in the prior art to employ, as automatic dishwashing detergents, alkaline detergent salts and mixtures of alkaline condensed phosphates, and alkaline detergent salts which may contain chlorinated trisodium phosphate. See, for example, US. Pat. No. 2,689,225. It is also known that such compositions can optionally, but advantageously, be formulated with suitable surface active agents as described in US. Pat. No. 2,895,916. Aqueous solutions of the aforementioned compositions have good detergency, readily remove objectionable stains from plastic and ceramic dinnerware and are easily rinsed from glasses, dishes and silverware Without leaving undesirable films, streaks or spots thereon. Although these compositions have many advantageous features, nevertheless, they have the undesirable feature of foaming in the presence of raw egg soil. Since foaming can reduce the efficiency of the automatic dishwashing machine by retarding the mechanical action of the fine water sprays and by reducing the rate of rotation of the perforated spray arms in certain types of machines, it would be advantageous, therefore, to provide an automatic dishwashing detergent which does not foam excessively in the presence of raw egg soil or other proteinaceous matter.

In accordance with US. Pat. No. 3,314,891, the foaming characteristics of an aqueous solution of an automatic dishwashing detergent containing alkaline detergent salts are substantially reduced in the presence of proteinaceous soil when this detergent is formulated with a composition containing a nonionic surface active agent and at least one alkyl phosphate ester having 18 carbon atoms in the alkyl radical or, more specifically, selected from the group consisting of stearyl acid phosphate and oleyl acid phosphate.

While the alkyl phosphate ester having 18 carbon atoms in the alkyl radical is very elfective, it does present a problem due to its insolubility and lack of dispersibility 3,741,912 Patented June 26, 1973 in the nonionic surface active agent and results in segregation during storage, thus causing problems in subsequent handling and formulating.

Accordingly, it is a purpose of the instant invention to provide a composition which, when formulated with an automatic dishwashing detergent, will reduce foam during use thereof in the presence of proteinaceous matter and wherein problems presented by insolubility of alkyl phosphate esters having 18 carbon atoms in the alkyl radical are eliminated or substantially reduced.

In accordance with the instant invention, it has now been discovered that oxyethylated mono or di alkyl amines or oxyethylated mono or di (hydroxy alkyl) amines, i.e., polyoxyethylene condensates of alkyl or hydroxy alkyl amines having from 10 to 20 carbon atoms in each alkyl group and from 1-50 ethenoxy units in the oxyethylene portion, perform as elfective dispersants for the alkyl phosphate ester having 18 carbon atoms in the alkyl radical. More particularly, the oxyethylated alkyl amines are characterized by the following structural formulae:

(om-omoun (CHf-CH20) H wherein R is an alkyl group having from about 10 to 20 carbon atoms and wherein n ranges from 2 to 5 and x+y+z range from 1 to 50.

It is essentially, in order to fully disperse the alkyl phosphate ester to employ a weight ratio of the alkyl phosphate ester to the oxyethylated alkyl amine of from about 2:1 to 1:2. Outside of this range satisfactory dispersion is not obtained.

The nonionic surface active agents which are advantageously employed in the compositions of the invention are generally the polyoxyalkylene adducts of hydrophobic bases wherein the oxygen/carbon atom ratio in the oxyalkylene portion of the molecule is greater than 0.40. Those compositions which are condensed with hydrophobic bases to provide a polyoxyalkylene portion having an oxygen/carbon atom ratio greater than 0.40 include ethylene oxide, butadiene dioxide and glycidol, mixtures of these alkylene oxides with each other and with minor amounts of propylene oxide, butylene oxide, amylene oxide, styrene oxide, and other higher molecular weight alkylene oxides. .Ethylene oxide, for example, is condensed with the hydrophobic base in an amount sufficient to impart water dispersibility or solubility and surface active properties to the molecule being prepared. The exact amount of ethylene oxide condensed with the hydrophobic base will depend upon the chemical characteristics of the base employed and is readily apparent to those of ordinary skill in the art relating to the synthesis of oxyalkylene surfactant condensates.

Typical hydrophobic bases which can be condensed with ethylene oxide in order to prepare nonionic surface active agents include monoand polyalkyl phenols, polyoxypropylene condensed with a base having from about 1 to 6 carbon atoms and at least one reactive hydrogen atom, fatty acids, fatty amides and fatty alcohols. The hydrocarbon others such as the benzyl or lower alkyl ether of the polyoxyethylene surfactant condensates are also advantageously employed in the compositions of the invention.

Among the suitable nonionic surfactants are the polyoxyethylene condensates of alkyl phenols having from about 6 to 20 carbon atoms in the alkyl portion and from about to 30 ethenoxy groups in the polyoxyethylene radical. The alkyl substituent on the aromatic nucleus may be octyl, diamyl, n-dodecyl, polymerized propylene such as propylene tetramer and trimer, isooctyl, nonyl, etc. The benzyl ethers of the polyoxyethylene condensates of monoalkyl phenols impart good properties to the compositions of the invention and a typical product corresponds to the formula:

Ca u (0 01120 915 GH2C6H6 Higher polyalkyl oxyethylated phenols corresponding to the formula:

O(CHZCHZO)nH R1 wherein R is hydrogen or an alkyl radical having from about 1 to 12 carbon atoms, R and R are alkyl radicals having from about 6 to 16 carbon atoms and n has a value from about 10 to 40, are also suitable as nonionic surfactants. A typical oxyethylated polyal'kyl phenol is dinonyl phenol condensed with 14 moles of ethylene oxide.

Other suitable nonionic surface active agents are cogeneric mixtures of conjugated polyoxyalkylene compounds containing in their structure at least one hydrophobic oxyalkylene chain in which the oxygen/carbon atom ratio does not exceed 0.40 and at least one hydrophilic oxyalkylene chain in which the oxygen/carbon atom ratio is greater than 0.40.

Polymers of oxyalkylene groups obtained from propylene oxide, butylene oxide, amylene oxide, styrene oxide, mixtures of such oxyalkylene groups with each other and with minor amounts of polyoxyalkylene groups obtained from ethylene oxide, butadiene dioxide, and glycidol are illustrative of hydrophobic oxyalkylene chains having an oxygen/carbon atom ratio not exceeding 0.40. Polymers of oxyalkylene groups obtained from ethylene oxide, butadiene dioxide, glycidol, mixtures of such oxyalkylene groups with each other and with minor amounts of oxyalkylene groups obtained from propylene oxide, butylene oxide, amylene oxide and styrene oxide are illustrative of hydrophilic oxyalkylene chains having an oxygen/ carbon atom ratio greater than 0.40.

Among the conjugated polyoxyalkylene compounds which can be used in the compositions of the invention are those which correspond to the formula:

wherein Y is the residue of organic compound having from about 1 to 6 carbon atoms and one reactive hydrogen atom, n has an average value of at least about 6.4 as determined by hydroxy number and m has a value such that the oxyethylene portion constitutes about 10 to 90 weight percent of the molecule. These surface active agents are more particularly described in US. Pat. No. 2,677,700.

Other conjugated polyoxyalkylene surface active agents which are most advantageously used in the compositions of the invention correspond to the formula:

wherein Y is the residue of an organic compound having from about 2 to 6 carbon atoms and containing x reactive hydrogen atoms which x has a value of at least about 2, n has a value such that the molecular weight of the polyoxypropylene hydrophobic base is at least about 900 and m has a value such that the oxyethylene content of the molecule is from about 10 to weight percent. Compounds falling within the scope of the definition for Y include, for example, propylene glycol, glycerine pentaerythritol, trimethylolpropane, ethylene diamine and the like. As already noted, the oxypropylene chains optionally, but advantageously, contain small amounts of ethylene oxide and the oxyethylene chains also optionally, but advantageously, contain small amounts of alkylene oxides such as propylene oxide and butylene oxide. These compositions are more particularly described in US. Pat. No. 2,674,619. Additional conjugated polyoxyalkylene surface active agents which are advantageously used in the compositions of this invention correspond to the formula:

wherein P is the residue of an organic compound having from about 8 to 18 carbon atoms and containing x reactive hydrogen atoms in which 2: has a value of 1 or 2, n has a value such that the molecular weight of the polyoxypropylene portion is at least about 58 and m has a value such that the oxyethylene content of the molecule is from about 10 to 90 weight percent and the formula:

wherein P is the residue of an organic compound having from about 8 to I18 carbon atoms and containing at reactive hydrogen atoms in which x has a value of 1 or 2, n has a value such that the molecular Weight of the polyoxyethylene portion is at least about 44 and m has a value such that the oxypropylene content of the molecule is from about 10 to 90 weight percent. In either case the oxypropylene chains may contain optionally, but advantageously, small amounts of ethylene oxide and the oxyethylene chains may contain also optionally, but advantageously, small amounts of alkylene oxides such as propylene oxide, butylene oxide and higher alkylene oxides containing 8 to 18 carbon atoms in the alkyl chains.

Thus, cogeneric mixtures of conjugated polyoxyalkylene compounds containing in their structure the residue of an active hydrogen-containing compound and at least one hydrophobic chain of units selected from the group consisting of oxypropylene and oxypropylene-oxyethylene units in which the oxygen/ carbon atom ratio does not exceed 0.40 and at least one hydrophilic chain of units selected from the group consisting of oxyethylene and oxyethylene-oxypropylene units in which the oxygen/carbon atom ratio is greater than 0.40 are suitable nonionic surface active agents.

Further suitable nonionic surface agents are the polyoxyethylene esters of higher fatty acids having from about 8 to 22 carbon atoms in the acyl group and from about 8 to 30 ethenoxy units in the oxyethylene portion. Typical products are the polyoxyethylene adducts of tall oil, rosin acids, lauric, stearic and oleic acids and the like. Additional nonionic surface active agents are the polyoxyethylene condensates of higher fatty acid amides having from about 8 to 22 carbon atoms in the fatty alkyl or acyl group and about 10 to 30 ethenoxy units in the oxyethylene portion. Illustrative products are coconut oil fatty acid amides condensed with about 10 to 30 moles of ethylene oxide.

Other suitable polyoxyalkylene nonionic surface active agents are the alkylene oxide adducts of higher aliphatic alcohols and thioalcohols having from about 8 to 22 carbon atoms in the aliphatic portion and about 3 to 50 oxyalkylene units in the oxyalkylene portion. Typical products are synthetic fatty alcohols, such as n-decyl, nundecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-hexadecyl, n-octadecyl and mixture thereof condensed with 3 to 50 moles of ethylene oxide, a mixture of normally fatty alcohols condensed with 8 to 20 moles of ethylene oxide and capped with benzyl halide or an alkyl halide, a mixture of normal fatty alcohols condensed with 10 to 30 moles of a mixture of ethylene and propylene oxides, a mixture of several fatty alcohols condensed sequentially with 2 to moles of ethylene oxide and 3 to 10 moles of propylene oxide, in either order; or a mixture of normal fatty alcohols condensed with a mixture of propylene and ethylene oxides, in which the oxygen/carbon atom ratio is less than 0.40, followed by a mixture of propylene and ethylene oxides in which the oxygen/ carbon atom ratio is greater than 0.40, or a linear secondary alcohol condensed with 3 to 30 moles of ethylene oxide, or a linear secondary alcohol condensed with a mixture of propylene and ethylene oxides, or a linear secondary alcohol condensed with a mixture of ethylene, propylene, and higher alkylene oxides.

The preferred alkyl phosphate esters which are used in the compositions of this invention are predominantly monostearyl phosphate which can contain, in addition thereto, diand tristearyl phosphates and monoleyl phosphates which can contain, in addition theretodiand trioleyl phosphates.

The alkyl phosphate esters available on the market are generally mixtures of monoand dialkyl phosphate esters which may also contain some trialkyl phosphate. For purposes of this invention the preferred alkyl phosphate ester compositions can contain, in addition to the monoalkyl phosphate, up to about 50 mole percent of the dialkyl phosphate and up to about 5 weight percent of the trialkyl phosphate. In a preferred embodiment of this invention, at least 50 mole percent of the stearyl acid phosphate component is the monostearyl phosphate.

The salts and particularly the alkali metal salts of the alkyl phosphate esters may also be employed as is apparent to anyone skilled in the art. Accordingly, the expressions stearyl acid phosphate and oleyl acid phosphate, as used herein, include the salts of the stearyl and oleyl acid phosphates.

The compositions of the invention generally contain from about 95 to 99.5 weight percent of the nonionic surface active agent and from about 0.5 to 5.0 weight percent total of the alkyl phosphate ester plus the oxyethylated alkyl amine. As previously stated, the ratio of the alkylphosphate ester to the oxyethylated alkyl amine must be from about 2:1 to 1:2. The compositions are readily prepared by blending the ingredients in the aforementioned proportions. The composition is then added to the automatic dishwashing detergent in order to reduce foaming during use thereof.

The automatic dishwashing detergents to which the compositions of the invention are added in order to reduce foaming of aqueous solutions thereof in the presence of raw egg soil generally contain 0 to 95 weight percent of an alkaline condensed phosphate salt such as tetrasodium pyrophosphate and those polyphosphates of the calcium and magnesium ion sequestering type whose Na O/P O ratios range from 1:1 to 1.67:1 and 5 to 100 weight percent of an alkaline detergent salt such as sodium carbonate, sodium bicarbonate and mixtures thereof, diand trisodium orthophosphate, sodium metasilicate, sodium sesquisilicate, borax and sodium borate. In addition, these detergents often include 5 to weight percent chlorinated trisodium phosphate. A mixture of ltihium hypochlorite or chlorinated cyanuric acid and trisodium phosphate can be used in place of chlorinated trisodium phosphate. An automtaic dishwashing detergent of this type can be prepared by adding an aqueous silicate solution to substantially anhydrous sodium tripolyphosphate and subsequently adding chlorinated trisodium phosphate thereto under the conditions as described in U.S. Pat. No. 2,895,916.

The foam characteristics of the detergent compositions may be measured by observing the rate of rotation of the perforated spray arm of an automatic dishwashing machine during the washing cycle in which raw egg soil and detergent are present in definitive quantities. The rate of rotation of the spray arm is, of course, inversely proportional to the amount of foam present. In each of the subsequent examples, foam evaluation is carried out in a Hobart Kitchen Aid dishwasher, The procedure followed is to turn on the machine and, after part of the water had been added, turn off the machine and add the detergent composition and additives, if any, and 15 cc. of raw egg. The dishwasher is then turned on again and the balance of the water added. The water temperature is indicated in the examples. After the washing cycle starts, the rate of rotation of the perforated spray arm is measured from the first to the second minute and from the third to the fourth minute. The average of these two rates is used as the spray arm rotation for the test. A spray arm rotation of about 70 r.p.m. or more is indicative that foam formation is being substantially depressed.

The following examples further illustrate the invention. The stearyl acid phosphate used in these examples contains 78% by weight monostearyl acid phosphate, 17% by weight distearyl acid phosphate, balance tristearyl acid phosphate, phosphoric acid and mipurities.

EXAMPLE 1 One and one-half parts by weight of a stearyl acid phosphate composition is added to a 500-ml. beaker along with parts by weight of a primary oxyalkylated alcohol (referred to hereinafter as Nonionic l) which is a condensate of a mixture of by weight 25 parts ethylene oxide and 50 parts propylene oxide with 25 parts of a mixture of normal fatty alcohols having from 12 to 18 carbon atoms. The beaker is then heated in an oven at 100 C. for an hour thereby completely melting the stearyl acid phosphate. 1.5 parts by weight of an oxyethylated alkyl amine is added to the beaker and placed in a 100 C. oven for another hour with continuous shaking of the container. The oxyethylated alkyl amine which is referred to hereinafter as oxyethylated alkyl amine No. 3 has the following formula:

When a portion of. the dispersed product is poured into a small jar and subjected to six freeze-thaw cycles of 60 minutes each, the product remains completely dispersed.

Dispersions employing between 1.5% and 3% by weight of the stearyl acid phosphate composition and which contain no oxyethylated alkyl amine separate after six of the above-described freeze-thaw cycles.

0.6 gram of the above product, including both the stearyl acid phosphate composition and the oxyethylated alkyl amine, is formulated with 16 grams of a composition referred to herein as Composition A containing the following ingredients in the proportions set forth below.

Composition A: Percent by weight The above formulated composition when evaluated for foaming characteristics in the presence of raw egg soil in a Hobart dishwasher in accordance with the procedure previously outlined achieved the results set forth in Table I below. The average r.p.m. shown in Table I below is an average of the spray arm speeds for the second and fourth minutes of a washing cycle.

TABLE 1 F.: Average r.p.m. 120 74 It will be noted from Table 1 above that the compositions of this invention when formulated with a conventional dishwashing detergent composition had good foam suppressing effect in the presence of egg soil. In all cases the average r.p.m. was above 70 and thus the composition compared favorably with the results achieved in the examples set forth in Schmolka et a1. patent US. 3,314,891. However, as can be seen from the stability tests the composition including the oxyethylated alkyl amine exhibits a high degree of stability in nonionic surface active agent whereas the otherwise identical composition which does not include the oxyethylated amine is not stable.

EXAMPLES 2-18 Examples of additional foam suppressing compositions embodying the principles of this invention are prepared from the nonionics indicated in Table 11 below, stearyl acid phosphate and the oxyethylated alkyl amines indicated in Table II below in the proportions shown in Table II below in terms of percent by weight. 0.6 gram of each of the foam suppressing compositions of Examples 2-18 are formulated with 16 grams of the base detergent referred to as Composition A in Example 1. These formulations are all tested in a Hobart Kitchen Aid dishwasher in the manner described above and the results in terms of the average of the r.p.m. for the first and third minutes are indicated in Table II below.

The nonionic surface active agents indicated by the numbers ranging from 1 to 3 in Table II below are as follows:

Nonionic 1 is described above in Example 1.

Nonionic 2 defines a heteric conjugated polyoxyalkylene polyol wherein a mixture of 90 weight percent propylene oxide and weight percent ethylene oxide is is condensed with trimethylolpropane so as to provide a hydrophobic base having a molecular weight of about 3200 and a mixture of 90 weight percent ethylene oxide and 10 weight percent propylene oxide is subsequently condensed with the hydrophobic base so as to provide a hydrophilic portion having a molecular weight of about 1280.

Nonionic 3 defines the polyethylene adduct of a polyoxypropylene hydrophobic base having a molecular weight of about 1750 wherein the oxyethylene content is about 20 weight percent of the molecule.

The oxyethylated synthetic alkyl amines indicated by the numbers 1 through 3 are as indicated below.

Number 1 is defined by the following formula:

(CHz-CH;O)2H

(CHg-CH20)3H Number 2 defines a tertiary amine having a fatty alkyl group derived from tallow and two polyoxyethylene groups attached to the nitrogen. The general formula is:

/(CH2OH2O),H R-N\ (OHz-CH2O) H wherein R represents the radical derived from the tallow and x plus y=5.

Number 3 is described above in connection with Example 1.

Excellent results are also achieved employing an amine having the formula of Number 2 above wherein R represents the lauryl radical.

TABLE II oxyethylated Stearyl N onionie alkyl amino acid Water phostemper- Ex. Deslg- Per- Desig- Perphate, Average, ature, No nation cent nation cent percent r.p.rn. F.

All the compositions of Table I 1 are stable, that is to say, do not separate out on standing.

The composition of this invention may be employed as previously stated with any commercial dishwashing composition, examples of which are as follows:

Composition B: Parts by weight Sodium tripolyphosphate 41.80 Trisodium phosphate .10 hydrate 11.30 Sodium metasilicate, anhydrous 14.70 Sodium sulfate .51 Sodium chloride .12

Composition C:

Sodium tripolyphosphate 60 Sodium carbonate 20 Sodium metasilicate, anhydrous 20 Composition D:

Trisodium phosphate 20 Sodium tetraborate .5 hydrate 25 Sodium metasilicate, anhydrous 20 Sodium carbonate 35 Composition E:

Trisodium phosphate 20 Chlorinated trisodium phosphate 5 Sodium tetraborate .5 hydrate 25 Sodium metasilicate, anhydrous 20 Sodium carbonate 30 It is to be understood that various changes and modifications may be made in the foregoing composition and process without departing from the spirit and scope of the appended claims.

What is claimed is:

1. A composition adapted to be formulated with automatic dishwashing detergents for reducing foam during use thereof in the presence of proteinaceous matter comprising:

(A) about 95.0 to 99.5 weight percent nonionic surface active component, selected from the group consisting of (a) polyoxyethylene condensates of alkyl phenols having from about 6 to 20 carbon atoms in the alkyl portion and the benzyl ethers of said polyoxyethylene condensates of alkyl phenols,

(b) cogeneric mixtures of conjugated polyoxyalkylene compounds containing in their structure the residue of an active hydrogen-containing compound having from about 2-6 carbon atoms, at least one hydrophobic chain of units selected from the group consisting of oxypropylene and oxypropylene-oxyethylene units in which the oxygen/ carbon atom ratio does not exceed 0.40 and at least one hydrophilic chain of units selected from the group consisting of oxyethylene and oxyethylene-oxypropylene units in which the oxygen/carbon atom ratio is greater than 0.40,

(c) polyoxyethylene esters of higher fatty acids having from about 8 to 22 carbon atoms in the acyl group,

(d) polyoxyethylene condensates of higher fatty amides having from about 8 to 22 carbon atoms in the fatty acyl group, and

(e) alkylene oxide adducts of higher aliphatic compounds selected from the group consisting of alcohols and thioalcohols having from about 8 to 22 carbon atoms in the aliphatic portion, and

(B) about 0.5 to 5.0 weight percent of (a) alkyl phosphate ester having 18 carbon atoms in the alkyl radical plus (b) oxyethylated amine selected from the group consisting of (CHr-CHzOhH ori -011 mm \N(CH2CH2 O nH wherein R is an alkyl group having from about 10 to 20 carbon atoms and wherein n ranges from 2 to 5 and x+y+z range from 1 to 50,

10 the weight ratio of said alkyl phosphate ester (a) to said oxyethylated alkyl amine (b) being from about 2:1 to 1:2.

2. A composition in accordance with claim 1 wherein said alkyl phosphate ester component consists essentially of up to about mole percent dialkyl phosphate, up to about 5 weight percent trialkyl phosphate, balance monoalkyl phosphate.

3. The composition of claim 2 wherein said alkyl phosphate ester is stearyl acid phosphate.

4. A low-foaming, automatic dishwashing detergent, characterized by low foaming in the presence of proteinaceous matter consisting essentially of (I) about to 99.9- weight percent liquid of a composition containing (A) 5 to 100 percent of an alkaline detergent salt selected from the group consisting of sodium carbonate, sodium bicarbonate, modified soda, disodium orthophosphate, trisodium orthophosphate, sodium metasilicate, sodium sesquisilicate, waterglass, borax, sodium borate, and mixtures thereof, and

(B) 0 to weight percent of an alkaline condensed phosphate salt selected from the group consisting of tetrasodium pyrophosphate and those polyphosphates of the calcium and magnesium ion sequestering type whose Na O/P O ratios range from 1:1 to l:67:1, and

(II) about 0.1 to 20 Weight percent of the foam inhibiting composition of claim 1.

5. The composition of claim 4 wherein said alkyl phosphate ester is stearyl acid phosphate.

References Cited UNITED STATES PATENTS 3,314,891 4/1967 Schmolka 252156 LEON D. ROSDOL, Primary Examiner E. L. ROLLINS, Assistant Examiner US. Cl. X. R.

25299, 358, 548, DIG. .001 

